I have a 2004 Jeep TJ and this morning I went out to head to work and it won't turn over. The dash lights come on but when I turn the key nothing happens whatsoever. When I turn the key the dash lights go off and when I let up on the key the lights return. I'm thinking its a ground or power issue? About 6 weeks ago I did get stuck in some water so I'm wondering if there may be some corrosion? It's only 13 degrees out right now so I took my car to work and will start to try an diagnose the issue tonight when I get home from work. Any ideas where to start. I plan on cleaning the battery posts and then checking connections for corrosion. Thoughts??